As you probably know, mammals do not undergo parthenogenesis naturally. However, scientists have been able to create a mouse via parthenogenesis. The mouse embryo was created by combining genetically altered cells from two different female mice. As such, no male DNA contributed to this mouse.

A process called genetic imprinting is thought to be one of the major reasons why mammals do not undergo parthenogenesis. Some genes are turned on in dad's genome and some are turned off. The same goes for mom's genome. This is why you need DNA from both mom and dad to create a viable embryo. Otherwise you would be missing expression of certain genes, which would prevent the embryo from developing appropriately.

Some of these genes that are turned on/off (differentially expressed) are known. In the case of the mouse, scientists were able to express these imprinted genes appropriately in the embryo. The success rate was not that great ... but the mice that developed were able to have babies on their own (the natural way).